Are you planning to buy a wattmeter?
If your answer is in the affirmative, there are things you need to know before making your purchase decision – such as the basic features and the different types of watt meters available on the market.
For an outlander, a wattmeter is an electrical power measuring instrument used to measure Watt1 for all AC circuits. There are hordes of wattmeters covering the market – from Heathkit, Collins, Swan, Drake and New Viking – to MFJ, Diawa, Vectronics, Autek, Coaxial Dynamics, Palstar, Bird and Kenwood. Almost all of these manufacturers say that theirs is accurate on the frequency, while giving the highest reading. What is the real story, let’s find out. Types of Wattmeter Before you narrow down your choice of a standard wattmeter, you may want to explore the different types of wattmeters available on the market today.
1. Electrodynamics Wattmeter This wattmeter is one of the oldest and most used for measuring electrical power in AC circuits. It consists of a pair of fixed or current coils and a movable coil called a potential coil. The current coil is placed in series, while the potential coil or the moving coil is placed in parallel. Such an arrangement enables rotation of the potential coil at a limited angle, to an axis perpendicular to the fixed coils. In addition, a needle is placed in the wattmeter to indicate electric power.
2. Electronic Wattmeter This instrument is used to measure power at frequencies across the Electrodynamics Wattmeter. It is further divided into vacuum tubes and digital wattmeter, depending on the functions and functions performed by the wattmeter.
3. Vacuum tubes Due to their traditional design, this instrument can measure electrical power in the non-linear range of mains voltage and flat current curves.
4. Digital Wattmeter This simple yet optically isolated wattmeter is used to make accurate measurements of “real” power consumption, despite the presence of large reactive and DC components in the current drawn by the monitored load.
So there, now that you know about the different types of wattmeter, here are some tips to help your purchasing decision while buying a wattmeter from a reputable manufacturer.
o If you are planning to buy a wattmeter from manufacturers such as Coaxial Dynamics or Bird Electronic Corporation, it may be worth knowing that their “accuracy rating” of + or – 5% of full scale when the needle is between the scale is correct.
o If you want a measuring instrument that provides protection against the reverse damping effect, go for a cheap Putt-Putt wattmeter with cross pin.
o To measure the power of an individual appliance or at a specific outlet, use the plug-in wattmeter. This instrument can be used extensively around your office or computer room to test the usability of an outlet and the power consumption of electronic items connected to it. Plug-in wattmeters can detect damaged electronics or poor electrical wiring by calculating the power flow through a single outlet. One of the simplest and easiest-to-use wattmeters in this category includes the Kill-A-Watt EZ from PowerMeterStore.
o Professional quality portable wattmeters such as Test Equipment Depot and Bird Model 5000-EX digital wattmeter meet the needs of on-site “troubleshooting” for electricians, electrical repair crews and system troubleshooters.
o To keep up with your electricity bills, you use digital wattmeters that evaluate the total energy consumption of an electricity system. These instruments have readings that show where and how power is consumed. Some advanced models also allow the power monitor to make small changes in the electric power flow. Digital wattmeters like Energy Detective and EIG Shark 100 are quite furious in the market. The former is used to monitor a home office or a small business, while the latter is used for more robust applications, such as large companies or IT rooms.
o Digital frequencies (RF) wattmeters such as the Thomas Scherrer OZ2CPU are used to measure accurate RF power and gain in amplifiers, bandwidth in filters, transmitter power, Standing Wave Ratio (SWR) and loss.
o Some wattmeters such as Palstars PM2000A have a dual motion meter system that measures and shows forward as well as reflected electric power.
Finally, whatever decision you make, remember that wattmeters play an important role in the maintenance of large electrical systems. By measuring the total power of the system, these instruments act as one of the first lines of defense against electronic wear. How you use the instrument is also an important factor when deciding what type of wattmeter you need.